Individual devices and functions have to be assigned an internal number that is used to call them intenally. For this purpose, the following devices and functions receive internal numbers:
•User
•Groups
•Voice mailboxes
•Fax boxes
•Automatic receptions
•Conference rooms
•Call on hold
•Door stations
•Announcement outputs
•Short-code dialling numbers
With a few exceptions, it must also be possible to call these devices and functions from outside. For this purpose, the internal numbers have to be assigned in the call distribution (exchange line routing incoming).
It is a good idea to create a dial plan for all devices and functions for the internal numbers before allocation and to transmit them to the PBX. Support is to be found in the following overview showing available and used phone numbers:
•Monitoring and Overviews > Dial plan
The following rules have to be considered when creating internal numbers:
Rules for internal numbers
•Double allocation of a number is not possible.
•Two to four digit numbers in the range from 10 to 9999 are possible.
−Door numbers: Only two to three digit numbers are possible. When put together with the numbers of the door bell buttons, this creates 3 to 4-digit phone numbers.
−Call Parking: Only two to three digit numbers are possible. When put together with the ten possible park positions 0-9, this creates ten 3 to 4-digit phone numbers.
•Using numbers with few digits (two or three-digit numbers) inevitably restricts the possible supply of numbers requiring more digits. For example: the internal number 12 also occupies the internal numbers 120-129 and 1200-1299.
•The exchange line access number on the PBX is 0 in the factory settings. However, this can be changed. Changing the exchange line access number reduces the dial plan. For example: the exchange line access number 9 also occupies the internal numbers 90-99, 900-999 and 9000-9999.
•Each account can be assigned its own exchange line access number for targeted dialling via a specific account. Also this exchange line access number reduces the dial plan.
•Legal emergency numbers are entered without local area code. An emergency number from the range 10 to 9999 reduces the dial plan. For example: the emergency number 112 also occupies the internal numbers 112 and 1120-1129.